I have hidden the food for now. First time in 2 months since I had my office tank I have had this happen. I have a framed 8x10 thing I made listing what is in the tank and at the top and bottom in large font it says PLEASE DO NOT FEED THE FISH. Co-workers around my desk confirmed no one did during the day that they saw. I suspect either someone working after hours did, or perhaps a cleaning person. Maybe they brought their kid to work and wasn't paying attention to them, IDK. Either that or someone isn't owning up as I am clearly annoyed.

Still trying to figure out what happened at home...

April 21st, had the water tested at Petco. 0 Nitrites, everything else normal. No signs of any issues.

April 22, she started having issues with the food. Other fish did not. She would eat some of the pieces and spit others out. Thought it was just a problem with the size of the food.

April 25th, stopped eating altogether. Other fish still would eat. She would look like she was hungry but refuse to touch any of the food. Decided to switch to NLS.

April 27th, took the video, everything was looking fine. Added new light.

April 28th, switched to NLS. She ate a few pieces, so I thought everything was fine. Added new rock covered in Peacock Moss.

April 29th, she started acting different. Could be seen hiding under rock with moss, or hovering near top of water. Still not eating.

May 1st, brought home temp tank I use for water changes at work. 6 cup. Added new treated water from emergency supply. Still would not eat, but was looking ok. She would rest on the bottom.

I honestly have no idea - I'm very new to this myself - but hopefully someone else will have some ideas. Sounds to me like she had something before she came to you that the stress of being relocated may have brought out of hiding. I would just watch your other girl closely and hope for the best.

When we brought them home, she did not seem interested in eating. Once I put her and her sister in the 30gal tank, she became very active and normal.

I was actually considering not getting any more fish for the tank, and just keeping it all for her and her sister. I like other community fish, but they are just not as interactive as Bettas seem to be.

Hence why I give any pet... Fish or not... The best care I possibly can. I thought I was goving my beardie the best care - and I have - but I keep learning new thigs to improve his life. So, don't give up on fish. You will ALWAYS learn somethinf new to improve their life.

That is the thing most never realize. When you see their personality, their quirks, thy become more than "just a" anything. So the fact you were upset she died... Shows you aught to own them again. You have sympathy towards them. (Keep in mind not everyone cries this is not a stab at those who don't).